Valve is really working hard on the next Steam client updates and Steam Deck is also getting the latest fixes, most of the latest update is only relevant to the Steam client in Desktop mode.
General
Added soundtrack playback controls to the library and quick access menu
Steam Desktop Mode
Fixed issues with the main window rendering black due to GPU compositing being disabled
Fixed login dialog briefly showing when shutting down the Steam Client
Updated to some icons in the Settings dialog
The game is ready for preload & game released spotlight in the library will no longer show for users who own the game through family sharing
Added a 'Compatibility' tab to Settings where SteamPlay settings can be changed.
In-Game Overlay
Fixed overflow of friend icons
No longer close chat windows when toggling the visibility of the Friends List from the Toolbar
Added Players section and a button to view the Players dialog
Screenshot Manager
Screenshots now are letterboxed, instead of squished, if they are a different aspect ratio than 16:9
Fixed an issue where the Screenshot Manager would not switch to a new selection if it was already open
Players Dialog
Added users in the current game to the top of the list when sorted by time
Added friend status to the rightmost column